“Unless it is quickly addressed by the courts – in the near-term – Obama’s Carbon Rule will increase electricity prices for everyone and threaten the system’s reliability,” Bush said.

Unveiled last month, the Clean Power Plan imposes the first-ever federal limits on carbon emissions from existing US power plants, and would become hugely beneficial to renewables in the 2020s. The plan is a linchpin of what President Barack Obama hopes will be a lasting legacy on climate change.